One of the most difficult problems encountered by health care providers is the successful treatment of the so-called "carpal tunnel syndrome". This syndrome is defined as a median nerve compression neuropathy at the volar (palmar) aspect of the wrist where the nerve passes beneath the transverse carpal ligament. In general, carpal tunnel syndrome occurs when the median nerve is compressed as it passes through a narrow tunnel of bone and ligaments at the wrist. This median nerve conducts sensation from part of the hand, up the arm, to the central nervous system. When the nerve is compressed, the result is numbness, tingling, burning and pain in the fingers and the hand. Some of the causes of carpal tunnel syndrome include nerve compression when the lubricating lining around the tendons becomes thick and sticky due to the normal wear and tear of aging, or from repetitive hand movements, thus pressing the nerve against the tunnel. Another cause is bone dislocation and fracture due to previous dislocation or fracture of the wrist, causing bone to protrude into the tunnel and press against the nerve. Arthritis may also be present and consequently the tunnel becomes too narrow and puts pressure on the nerve. Another cause of the syndrome is fluid retention which causes swelling of the tissue in the carpal tunnel including, perhaps, the nerve itself. This occurs most often during pregnancy with the symptoms subsiding after the baby is born. Since the space in the carpal tunnel is limited, the injury to the structures is further aggravated by friction with other elements in the tunnel. The carpal tunnel is formed by the anterior concavity of the carpal bones and the flexor retinaculum (transverse carpal ligament). It is a space that has a cross-section that is approximately oval-shaped. This space is almost completely occupied by flexor tendons and the median nerve so that there is very little extra space when an injury occurs. The result is, therefore, that in this tightly constricted space, the median nerve and tendons further injure themselves by rubbing against each other. Prescribed treatment for the syndrome is, in general, to allow the swollen structures to heal up and thereby have its swelling reduced. However, since the hand is in use at all times and the structures move back and forth as the fingers and hand are articulated, it is difficult not to re-irritate the injured structures. Therefore, in the past, the treatment has been to provide a fixation of the important parts of the hand that cause the structures to move through the tunnel. The immobilization has been accomplished by the use of splints such as the "cockup splint" or by the use of a band tightly wrapped around the wrist. The inadequacies of both of these splints are that they limit the use of the hand which is being treated, they do nothing to support the normal biomechanics of the wrist, and they compress the anterior surface and, thereby, allow for further injury. U.S. Pat. No. 4,966,137 to Davini (the inventor of the present invention) presents a splint which obviates these and other difficulties that existed in prior art devices. The embodiment of the splint presented in the earlier Davini patent, while very effective, has a number of practical drawbacks. It involves a number of individual parts. It also requires a significant amount of material. Furthermore, the device must be provided in a number of sizes in order to adapt to various wrist sizes. Finally, the device can be somewhat difficult to apply and somewhat conspicuous in use.
It is, therefore, a principal object of the present invention to provide an improved splint system which gives improved successful treatment of carpal tunnel syndrome.
Another object of the invention is to provide an improved splint system for the prevention of carpal tunnel syndrome.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome without requiring immobilization of the hand and fingers.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome, which system can be worn during many activities that commonly cause the syndrome.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome, which system maintains and/or restores the size and shape of the carpal tunnel, thus allowing decompression of the involved injured structures and maintenance of normal structural relationships.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome, which system can be readily removed by the patient for washing and the like.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome in which the components of the system are constructed so as to form a unitary device, at least at the time of application of the system, instead of a device with more than one individual part.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome, which system is simple in construction, inexpensive to manufacture, and capable of a long life of useful service with a minimum of maintenance.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome, which system can be readily applied without the use of special equipment.
A further object of the invention is to provide an improved splint system for the treatment and prevention of carpal tunnel syndrome, which system can fit a wide range of wrist sizes.